Do i need a tetanus shot if my dog bit me on my hand. my dog who has been vaccinated, ?

Maybe: Any break in the skin can allow tetanus spores to enter & set up the process that triggers tetanus. If you had the primary series as a kid & no booster within 10 yrs it would be reasonable. Dog bites are more likely to introduce other bacteria for an infection & proper cleaning/local care may avoid any complication. The rest is your call. If you get a booster now you get 10 yrs from it also.